The configuration of such a puncture instrument would conventionally be as follows.
That is, it would comprise: a cylindrical main body case having a puncture aperture on the lower end side; a needle holder provided on the puncture aperture side inside the main body case; a first elastic object for moving the needle holder to the puncture aperture side; and a second elastic object for pulling the needle holder, moved to the puncture aperture side by the first elastic object, back to the upper end side inside the main body case (e.g. Patent document 1).    [Patent document 1] Japanese Patent Laid-Open Application No. 2002-085384